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111.
Auer Michael Hopfgartner Niklas Griffiths Mark D. 《International journal of mental health and addiction》2021,19(6):1939-1950
International Journal of Mental Health and Addiction - Online gambling has become increasingly popular over the past decade as has research using behavioural tracking (player account) data. To... 相似文献
112.
R.J. Simpson S. Akwei A.A. Hosseini S.T. MacSweeney D.P. Auer N. Altaf 《AJNR. American journal of neuroradiology》2015,36(6):1171
BACKGROUND AND PURPOSE:MR imaging–detected carotid plaque hemorrhage is associated with an increased risk of recurrent ischemic cerebrovascular events and could be an indicator of disease progression; however, there are limited data regarding the dynamics of the MR imaging–detected carotid plaque hemorrhage signal. We assessed the temporal change of this signal and its impact on carotid disease progression.MATERIALS AND METHODS:Thirty-seven symptomatic patients with 54 carotid stenoses of >30% on sonography underwent serial MR imaging during 24 months. A signal-intensity ratio of >1.5 between the carotid plaque and adjacent muscle was defined as plaque hemorrhage, and a change in signal-intensity ratio of >0.31 between time points was considered significant. Sixteen patients underwent ≥2 carotid sonography scans to determine the peak systolic velocities and degree of stenosis with time.RESULTS:Of the 54 carotids, 28 had the presence of hyperintense signal on an MR imaging sequence (PH+) and 26 had the absence of hyperintense signal on an MR imaging sequence (PH−) at baseline. The signal-intensity ratio was stable in 33/54 carotid plaques, but 39% showed a change. Plaque hemorrhage classification did not change in 87% of carotid plaques, but 4 became PH+, and 3, PH−. As a group, PH+ carotids did not change significantly in signal-intensity ratio (P = .585), whereas PH− showed an increased signal-intensity ratio at 24.5 months (P = .02). In PH+ plaques, peak systolic velocities significantly increased by 22 ± 39.8 cm/s from baseline to last follow-up sonography (Z = 2.427, P = .013).CONCLUSIONS:During 2 years, MR imaging–detected carotid plaque hemorrhage status remained stable in most (87%) cases with 4 (7%) incident plaque hemorrhages. PH+ plaques were associated with increased flow velocity during the follow-up period.Currently, the degree of ICA stenosis is the principal criterion on the basis of which the decision for carotid intervention is made. This is based on strong evidence from randomized controlled trials that carotid endarterectomy reduces stroke risk in patients with severe carotid artery stenosis.1,2 However, those studies also showed that a significant proportion of patients with symptomatic carotid disease will not have a recurrence. Subsequently, much research is focused on the identification of high-risk subgroups,3 especially for those with moderate or asymptomatic carotid stenosis.Plaque hemorrhage (PH) is implicated in carotid plaque vulnerability4 and is detectable by MR imaging.5,6 A recent longitudinal follow-up study and meta-analysis7 demonstrated that MR imaging–detected plaque hemorrhage (MR imaging-PH) strongly predicts recurrent ischemic events. The MR imaging-PH signal seems to be stable for 12 months,8 but stability of MR imaging-PH features beyond 12 months remains unclear. Knowledge of longer term stability of MR imaging-PH would be helpful if it is to be used to assist decision-making in interventions and to determine the need for follow-up imaging.Plaque volume progression on sonography recently has been shown to predict cerebrovascular events9; however, this measure was not used in the current study. Carotid stenosis progression has been suggested to be a better predictor of subsequent TIA/stroke than a single measurement.10 Although general carotid sonography surveillance may not be cost-effective,11 this situation may well be different for a subgroup of patients with a higher risk for stenosis progression. It is conceivable that MR imaging-PH is also an indicator of disease progression12 and, therefore, may be useful in this regard.The aim of this study was to determine MR imaging signal changes in the carotid artery plaque during 2 years and whether the presence of MR imaging-PH at baseline is associated with stenosis progression. 相似文献
113.
Acute myeloid leukemia with complex karyotypes and abnormal chromosome 21: Amplification discloses overexpression of APP, ETS2, and ERG genes 总被引:5,自引:0,他引:5
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Anti-CD2 and anti-CD3 induced T cell cytotoxicity of human intraepithelial and lamina propria lymphocytes. 总被引:8,自引:0,他引:8 下载免费PDF全文
The effector function of immunocompetent cells in the gut mucosa has not yet been defined. The cytotoxic function of these cells might be important in the normal immune response and could be relevant to the mucosal damage seen in inflammatory conditions. The cytotoxic function of isolated intraepithelial and lamina propria mononuclear cells in six and 18 hour assays after the addition of various stimuli that interact with the human leukocyte antigens CD2 and CD3 on the mucosal effector cells was investigated. T cell phenotypes were determined using CD4, CD8, and HML1 to characterise cells of the appropriate compartments. Anti-CD3 and phytohaemagglutinin can induce toxic activity of lamina propria lymphocytes in most individuals after six hours and in all individuals after 18 hours. Anti-CD2, anti-CD3, and phytohaemagglutinin are similarly effective at triggering lamina propria lymphocytes. Intraepithelial lymphocytes contain predominantly CD8 and HML1 positive T cells, differentiating phenotypically intraepithelial lymphocytes from lamina propria lymphocytes. Intraepithelial lymphocytes are not cytotoxic at six hours, but have a toxic function comparable with lamina propria lymphocytes after 18 hours with all three triggers. Intraepithelial lymphocytes from inflamed mucosa (Crohn's disease and diverticulitis) mediate significantly reduced cytotoxicity in vitro compared with normal mucosa, whereas lamina propria lymphocyte toxicity is not different. Reduced numbers of cytotoxic cells and reduced reactivity to the trigger substances used after in vivo activation or cold target inhibition could explain the observed differences between intraepithelial lymphocytes from inflamed and uninflamed mucosa. Changes in cell mediated cytotoxicity of intraepithelial lymphocytes and lamina propria lymphocytes may be involved in the mucosal damage in these inflammatory conditions. 相似文献
116.
Clinical efficacy and survival with first-line inhaled iloprost therapy in patients with idiopathic pulmonary arterial hypertension. 总被引:4,自引:0,他引:4
Christian F Opitz Roland Wensel J?rg Winkler Michael Halank Leonhard Bruch Franz-Xaver Kleber Gert H?ffken Stefan D Anker Abdissa Negassa Stephan B Felix Roland Hetzer Ralf Ewert 《European heart journal》2005,26(18):1895-1902
AIMS: To describe the long-term clinical efficacy of inhaled iloprost as first-line vasodilator mono-therapy in patients with idiopathic pulmonary arterial hypertension (IPAH). METHODS AND RESULTS: Seventy-six IPAH patients were prospectively identified and treated with inhaled iloprost. Clinical, haemodynamic, and exercise parameters were obtained at baseline, after 3 and 12 months of therapy and yearly thereafter. Four endpoints were prospectively defined as follows: (i) death, (ii) transplantation, (iii) switch to intravenous (i.v.) therapy, or (iv) addition of or switch to other active oral therapy. During follow-up (535+/-61 days), 11 patients died, six were transplanted, 25 were switched to i.v. prostanoids, 16 received additional or other oral therapy, and 12 patients discontinued iloprost inhalation for other reasons. Event-free survival at 3, 12, 24, 36, 48, and 60 months was 81, 53, 29, 20, 17 and 13%, respectively. Among haemodynamic and exercise parameters, mixed venous oxygen saturation (P<0.001), right atrial pressure (P<0.001), and peak oxygen uptake (P=0.002) were associated with event-free survival. CONCLUSION: In this study, only a minority of patients could be stabilized with inhaled iloprost mono-therapy during a follow-up period of up to 5 years. In the presence of multiple treatment options, chronic iloprost inhalation as mono-therapy appears to have a limited role. 相似文献
117.
118.
Canan Alhan Theresia M. Westers Eline M. P. Cremers Claudia Cali Birgit I. Witte Gert J. Ossenkoppele Arjan A. van de Loosdrecht 《British journal of haematology》2014,167(1):100-109
The estimation of survival of myelodysplastic syndromes (MDS) and risk of progression into acute myeloid leukaemia is challenging due to the heterogeneous clinical course. The most widely used prognostic scoring system (International Prognostic Scoring System [IPSS]) was recently revised (IPSS‐R). The aim of this study was to investigate the prognostic relevance of flow cytometry (FC) in the context of the IPSS‐R. Bone marrow aspirates were analysed by FC in 159 patients with MDS. A flow score was calculated by applying the flow cytometric scoring system (FCSS). Patients were assigned to IPSS and IPSS‐R risk groups. The FCSS correlated with the World Health Organization classification, IPSS and IPSS‐R risk groups. Mild flow cytometric abnormalities were associated with significantly better overall survival (OS) and lower risk of disease evolution. The presence of aberrant myeloid progenitors was associated with transfusion dependency and disease progression. Most importantly, the FCSS identified prognostic subgroups within the IPSS‐R cytogenetic good risk and low risk group. Flow cytometric analysis in patients with MDS provides additional prognostic information and is complementary to the IPSS‐R. The addition of a flow cytometric score next to the clinical parameters within the IPSS‐R is a further refinement of prognostication of patients with MDS. 相似文献
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120.